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When we add or subtract time, remember that we are working with hours, minutes and seconds.
60 seconds = 1 minute
60 minutes = 1 hour
Example: 1h 45min.+ 2h 36min. You will think of your own way to do this.
One way might be:
1h 45min. +2h 36min. = 3h 81min. (Notice: there is 1h hidden in those minutes.)
= 4h 21min.
7. Calculate the answers and write down your calculations:
7.1 53 min. and 48 sec. + 14 min. and 34 sec
7.2 14 h 25 min. － 7 h 36 min.
Activity 4:
To describe and illustrate ways of measuring and representing time in different cultures throughout history [LO 4.4]
ASSIGNMENT (RESEARCHBASED)
Your educator will help you to find reference books or take you to the library when you need information in this Assignment.
1. Read the following information.
People in the Ancient World did not have clocks and watches as we know them, but they did try to measure time. Some of their instruments for measuring time included: a sun dial; a water clock; a candle clock; burning oil and an hourglass. Some of them were not very accurate.
2. Look up information in reference books or on the computer to find out what these instruments looked like and how they worked. Also try to find out which people used them and where they lived.
3. Choose four of the instruments named in number 1. Draw them and label each drawing clearly.
4. Explain how any two of them worked.
5. Make either a water clock or a candle clock (or one of the others) and show it to the class. Explain to the class how it works.
6. In the table below write down which people used each of the clocks you have drawn and where they lived:
Name of clock  People who used it  Where they lived 
7. Explain why these ancient instruments were not always very accurate. Write your answer below.
8. Try to think of a link between one of them and a modern instrument which we use. Write down your answer .
LO 4 
measurementThe learner will be able to use appropriate measuring units, instruments and formulae in a variety of contexts. 
We know this when the learner: 
4.1 reads, tells and writes analogue, digital and 24hour time to at least the nearest minute and second; 
4.2 solves problems involving calculation and conversion between appropriate time units including seconds, minutes, hours, days, weeks, months and years; 
4.3 uses timemeasuring instruments to appropriate levels of precision, including watches and clocks; 
4.4 describes and illustrates ways of measuring and representing time in different cultures throughout history; 
4.5 estimates, measures, records, compares and orders twodimensional shapes and threedimensional objects using S.I. units with appropriate precision for:

4.6 solves problems involving selecting, calculating with and converting between appropriate S.I. units listed above, integrating appropriate context for Technology and Natural Sciences; 
4.7 uses appropriate measuring instruments (with understanding of their limitations) to appropriate levels of precision including:

4.8 investigates and approximates (alone and/or as a member of a group or team):

ACTIVITY 1
1.1 2
1.2 5
1.3 7
Practical work
TEST YOUR SKILLS
1.1 20 to 11 or 10.40
1.2 9.25 or 25 past 9
2 Drawing hands on clock faces (see module)
ACTIVITY 2
1.1 05:10
1.2 16:20
1.3 21:45
1.4 00:57 or 24:57
2.1 06:45
2.2 16:10
3.1 Drawing on clockface: ten to two in the afternoon
3.2 Drawing on a clockface: ten past nine in the morning
4. Morning; the hour hand is on the right side of the clockface; in the afternoon it would be on the left side of this clockface.
5.1 1 min. 17,53s
5.2 5 min. 56,01s
ACTIVITY 3 problems involving time
1.1 Kathleen
1.2 Her time is the shortest
1.3 0,9s
2. 13:00 or 1 p.m
3.1 Flight 502: afternoon; Flight 504: evening
4. 7 h 40 min.
5.1 8 April 2003
5.2 5 December 2003
5.3 10 days
5.4 3 weeks 3 days
5.5 1 weeks 2 day
( Note : from morning high tide to afternoon high tide on the same day the time seems to decrease by 1min.each day, but not on 3 July.)
7.1 1h 8 min. 22 s.
7.2 6 h 49 min.
ACTIVITY 4 assignments
1. Read
2. Look up information
3.1 Drawings
3.2 Practical and oral
3.3 Own – practical and oral
3.4 Own – complete table
4. They could not measure seconds and parts of seconds; outside conditions (e.g. wind) influenced the instruments.
5. hourglass; eggtimer
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